Corporeal access tube assembly

ABSTRACT

A corporeal access tube assembly including a tube segment in which a coil spring is embedded along a portion of the segment. A retention balloon is secured to the tube segment around a portion which does not contain the coil spring. The balloon is inflated into a preformed shape when in operation but its walls are not stretched to any noticeable extent. A bolus on one end of the tube segment includes a stylet pocket in which a stylet is inserted to stretch the balloon axially and decrease its size radially for purposes of insertion and removal of the tube assembly.

RELATED APPLICATIONS

This is a division of application Ser. No. 08/734,630, filed Oct. 18,1996, and entitled Corporeal Access Tube Assembly and Method, now U.S.Pat. No. 5,860,952 issued Jan. 19, 1998 which is a continuation-in-partof application Ser. No. 08/583,930, filed Jan. 11, 1996 and entitledReplacement Gastronomy Tube. The latter application is now Abandoned.

FIELD OF THE INVENTIONS

These inventions relate generally to medical catheters. They relateparticularly to catheters used to access either the stomach and/orintestine, or the bladder, through a stoma or ostomy in the abdominalwall.

BACKGROUND OF THE INVENTIONS

The need to artificially introduce food into the gastrointestinal tractsof individuals who can not eat, or will not eat, has been well knownthroughout and even prior to this century. Before the mid-1970's,feeding was done nasogastrically with red rubber or polyvinylchloridefeeding tubes. The use of enteral feeding by means of nasogastric tubesexpanded dramatically in the late 1970's with the introduction of tubesconstructed of either silicone rubber or polyurethane. Being constructedof stronger materials, these tubes incorporated thinner walls, and weretherefore smaller in outside diameter. These smaller tubes were easierto insert and more comfortable for the patient, and their introductionresulted in a very rapid growth of enteral nutrition via the nasogastricroute, and increased interest in enteral nutrition in general.

By the 1980's problems with nasogastric feeding were recognized byclinicians and the advantages of direct gastrostomy access into thestomach through the abdominal wall had been described by Vazquez in U.S.Pat. No. 4,356,824, and by Moss in U.S. Pat. No. 4,543,085. Refinementsin securing gastrostomy tubes in the patient were described by Parks inU.S. Pat. No. 4,666,433 and in U.S. Pat. No. 4,685,901.

The 1980's also saw the refinement of methods for forming thegastrostomy stoma. Prior to the 1980's, the stoma or gastrostomy wasformed surgically by the Stamm procedure, which required a surgicallaporatoratomy to insert the tube, usually a latex urologic Foleyretention catheter. A new method, called a "PEG", or PercutaneousEndoscopic Gastrostomy, eliminated the need for a surgical gastrostomyto place the gastrostomy tube and dramatically expanded the interest inthe use of direct gastrostomy tubes. The advantages of PEGs and the PEGtechnique were described by Quinn et al in U.S. Pat. No. 4,795,430. Theword "PEG" is used herein to identify both the tube and the procedure.

Gastrostomy tubes can generally be organized into three main groups, thethird of which includes two subgroups:

1. SPECIALTY TUBES placed at the time of gastric surgery by the Stammtechnique. The Moss and Vazquez patent tubes are examples of this type.

2. PEG tubes which are used to form the initial stoma or gastrostomy.

3. REPLACEMENT TUBES which are used to replace the PEG tube after aperiod of time because the PEG has worn out with use, or because adevice which is more specific to the patient's need is required. Thesetubes are inserted into the original stoma created by either the PEG orthe Stamm technique.

a. LOW PROFILE REPLACEMENT TUBES which are preferred for active patientswho wish to conceal the tube's outer fitments during periods when theyare not receiving feeding formula. The background for this type ofreplacement tube is described by Quinn et al in U.S. Pat. No. 5,125,897.

b. SIMPLE REPLACEMENT tubes which are less complicated and lessexpensive are used for patients who are not active and have no need tohide their device. These devices are direct modifications of theoriginal urologic Foley catheters used in early gastrostomies. They aredescribed by Parks in U.S. Pat. No. 4,666,433.

With some exceptions within individual designs, gastrostomy tubes ortube assemblies of the aforedescribed types each incorporate thefollowing seven features or components:

1. A tube to carry the enteral feeding formula into the stomach and orthe intestine.

2. An outflow port in the distal end of the tube. The port or ports maybe incorporated in the end or the side wall of the tube. They may alsobe incorporated in a separate, molded bolus fastened to the distal endof the tube.

3. An administration set connector attached to the proximal end of thetube, which is outside of the patient.

4. A distal end retention device to hold the tube in the stomach, e.g.,an inflatable balloon or a molded retention shape which can be deformedwith a stylet for insertion and removal.

5. An external bolster to secure the tube at the point where it exitsthe skin. This bolster maintains the proper distance between theexternal bolster and the internal retention device, a distancecorresponding to the combined thickness of the individual patient'sskin, abdominal wall and stomach wall at the site of the gastrostomy.

6. An anti-reflux valve to prevent leakage of gastric acids from thepatient when the administration set is being changed or when violentcoughing causes excessive back pressure.

7. A measurement system to measure the patient's abdominal wallthickness so that the tube length between the retention device and theexternal bolster can be adjusted to match this thickness.

Just as gastrostomy tubes or tube assemblies are used for enteralfeeding, so suprapubic catheter tubes or tube assemblies are used toadminister drugs to, or drain urine from, the bladder. Such tubes ortube assemblies comprise the same seven features or components referredto above in the context of gastronomy tubes or tube assemblies. However,they access the bladder through a stoma formed in the abdominal wallabove the bladder or pubic area.

SUMMARY OF THE INVENTION

The present inventions seek to resolve problems which clinical practicehas shown to be inherent in the aforedescribed seven features orcomponents of different types of known gastrostomy and suprapubiccatheterization tubes or tube assemblies. As described in the backgroundmaterials, there is now little key component design commonality betweenPEGs, low profile replacement tubes and simple replacement tubes, forexample. The inventions disclosed herein embody improvements which canbe incorporated into all of the tube types, thereby providing a commoncomponent system for all gastrostomy and superpubic catheterizationtubes.

In doing so these inventions overcome the major problems associated withexisting tubes, which are:

Difficulty of insertion and removal.

Difficulty of obtaining accurate measurement of required tube depth.

Lack of durability of internal retention devices.

Incompatibility of replacement gastrostomy tubes with PEGs.

Valve failure.

Infection of the stoma.

Difficulty in cleaning of the stoma.

The need for many tube sizes.

Inability to secure the tube adequately with an external bolster.

The need for special administration sets.

These problems manifest themselves in tube components as follows:

1. THE TUBE. Silicone and polyurethane are the materials of choice forthese tubes. Silicone is softer and more compliant than polyurethane.Silicone has a lower modulus of elasticity than urethane. Softness isdesirable in medical catheters. However, softness also increases theability to kink and collapse, which are undesirable characteristics.These problems have heretofore been addressed by making tube wallsthicker in silicone tubes or by constructing the tubes from thestronger, but less flexible, polyurethane. The designer has had to makea choice between a smaller, but less flexible, urethane tube and alarger, softer silicone tube.

Flexibility, resistance to kinking and resistance to collapsing arecharacteristics which are particularly important in gastrostomy andsuprapubic catheterization tubes. Because these tubes exit the bodyperpendicular to the skin, it is desirable to be able to bend them asclose to a right angle as possible so that they can lie next to theskin. This problem is addressed in Quinn et al U.S. Pat. No. 4,834,712.In addition, some forms of gastrostomy tubes have extensions which feedout of the stomach into the duodenum or jejunum. These tube extensionsmust be able to negotiate from one to five acute angle turns, dependingwhether they are placed in the duodenum or further into the jejunum.Tubes with a higher modulus, i.e., less flexible tubes, can dig into theside walls of the intestine and resist making the required tight turnsas they move through the intestine.

2. OUT FLOW PORT IN DISTAL END OF TUBE. The problems with conventionalnasogastric feeding tube outlet ports as to insertion, flow and cloggingare described by Andersen et al. in U.S. Pat. No. 4,594,074. Theseproblems are also common to gastrostomy tubes.

3. ADMINISTRATION SET CONNECTOR. Existing low profile tubes haveadministration set connectors which exit perpendicular to the patient'sskin. This configuration is described in Quinn et al. U.S. Pat. No.5,125,897. To prevent the administration set from kinking and twisting,special sets with right angle connectors must be used so that theadministration set tubing can lie comfortably on the patient's abdomen.

4. DISTAL END RETENTION DEVICE TO HOLD THE TUBE IN THE STOMACH orbladder. Tubes with inflatable silicone retention balloons are easy toinsert because the uninflated balloons are formed completely flatagainst the tube wall. However, they are unreliable because the siliconeballoon walls which are stretched thin tend to break easily. In additionthey must incorporate a second inflation lumen in the tube to access theballoon. This feature makes the tube larger and also requires theincorporation of a balloon inflation valve which adds cost and bulk tothe product.

Pre-formed, molded internal retention devices must be deformed with astylet and are difficult to insert and remove. They are generallyreliable once they are in place, however.

5. EXTERNAL BOLSTER. Existing technology for bolsters is well known, asthe aforementioned prior art illustrates. Some bolsters secure the tube,but do not bend it at a right angle to position it out of the way, nextto the skin. Others secure and bend it at a right angle, but are rigidparts which can be uncomfortable for the patient. None of these rigidbolsters achieve full, right-angle bending of the tube due to thestiffness of the tubing.

6. ANTI-REFLUX VALVE. Existing valves include flapper valves which clogand malfunction. Furthermore, it is often necessary to open the valve todecompress the stomach or bladder, so location of the valve is alsoimportant. Some gastrostomy valves are positioned so that specialdecompression sets are required to activate them if feeding is nottaking place.

7. TUBE MEASUREMENT AND SIZING. PEGs and simple gastrostomy tubes, forexample, are sized to the patient after they are inserted. The positionof the external bolster is approximated by simultaneously tugging on theinternal retention member and then pushing the external member down onthe skin. This is an imprecise method. Low profile replacement tubeshave separate stoma depth measuring tools which are pre-inserted intothe stoma. The clinician then selects a tube which corresponds to thismeasurement from a large selection of tube lengths. These tubes can notbe adjusted for a change in patient size.

The present inventions include a reinforced silicone tube which has thesame modulus as an unreinforced silicone tube and walls which can not becollapsed or kinked. The invention has walls which are approximately thesame thickness as a comparable urethane tube. The new tube is thereforesuperior to both silicone and urethane.

The present inventions include a one piece anti-reflux slit valvelocated in the set which automatically opens flow in either directionwhen the luer of a regular set connector is inserted. It cannot bedamaged by a stylet.

The present inventions include a pre-formed, pre-inflated siliconeballoon with unique deformation characteristics for both insertion andremoval. Because it is pre-formed, the balloon walls are approximately0.012 to 0.030 inches thick during use, versus the 0.004 inch thickwalls of inflated balloons. It also has unique retention qualities inrelation to much larger retention devices.

The present inventions include a simple, silicone bolster which bothsecures the catheter and bends it at a right angle to the patient'sskin. The bolster presents minimum bulk and maximum access to the stomafor air circulation and cleaning. It is secure but can be easilyadjusted as the patient's condition changes.

The present inventions include a system which eliminates the need forpre-measurement devices and greatly reduces the number of necessarysizes for low profile replacement tubes. For the first time, it alsoprovides a means for precisely measuring the bolster position. Thispre-measurement and precise bolster positioning are accomplished by aunique tube marking system in combination with the bolster.

In addition to the aforedescribed, these improvements and others arealso embodied in a PEG tube and insertion assembly invention. Thisinvention incorporates most of the components of the low profilereplacement tube. After insertion, the PEG tube assembly which remainsembodies all of the features of the replacement tube.

The PEG tube assembly is inserted by the same method as a conventionalPEG. Therefore no stylet is required. In addition, because the internalretention balloon is inserted in its inflated state, the feeding setconnector has no inflation/deflation valve or lumen.

After insertion into the stomach, the tube is cut off at a predeterminedpoint indicated by a wide black marker band encircling the PEG tube. Aninflation/deflation lumen in the wire reinforced PEG tube is occluded bya plug extending approximately 5 centimeters below the black markerband. This plug retains the air in the retention balloon when the tubeis subsequently cut at the marker band.

After the tube is cut at the marker band, the external bolster of theinvention and retention ring are slipped over the tube. The feeding setconnector is then threaded into the tube. Tube depth is adjusted and theexternal bolster is anchored. The device is now ready to function as alow profile gastrostomy tube, just like the replacement tube.

To remove the tube, it is cut off at a marker line below the markerband. This line is normally positioned 10 to 15 centimeters from theretention balloon. The marker line is below the air inflation/deflationline plug, so the air line is opened when the tube is cut. The open airline allows air to escape from the balloon during removal, therebyallowing the balloon to deform as it is being pulled out of the stoma.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects of these inventions are illustrated moreor less diagrammatically in the drawings, in which:

FIG. 1 is an illustration of a replacement tube assembly embodyingfeatures of the inventions, with the tube assembly in place accessing apatient's stomach;

FIG. 2 is an enlarged side elevational view of the replacement tubeassembly illustrated in FIG. 1;

FIG. 3 is a longitudinal sectional view through the bolus end of thereplacement tube assembly illustrated in FIGS. 1 and 2;

FIG. 4 is a top plain view of the bolus end illustrated in FIG. 3;

FIG. 5 is a longitudinal sectional view, similar to FIG. 3, showing moreof the replacement tube assembly embodying features of the inventions;

FIG. 5A is sectional view taken through the tube assembly of FIG. 5,showing the coil spring.

FIG. 6 is a side view, similar to FIG. 2 but partially in sectionillustrating a near-completely assembled replacement tube assemblyembodying features of the inventions;

FIG. 7 is an end view of the set-connector cap in the replacement tubeassembly of FIGS. 1-6;

FIG. 8 is an enlarged, side view of a set-connector for the replacementtube assembly of FIGS. 1-6, partially in section;

FIG. 9 is a side elevational view of a replacement tube assemblyembodying features of the inventions, illustrated in its unassembledform prior to insertion through a stoma formed in a patient's stomach;

FIG. 10 is a front elevational view of the bolster component for thereplacement tube assembly of FIG. 9 taken along line 10--10 of FIG. 9,with the tube component removed;

FIG. 11 is a bottom plan view of the bolster component of FIG. 10, takenalong line 11--11 of FIG. 9 with the tube component removed;

FIG. 12 is a longitudinal section taken through the replacement tubeassembly of FIG. 9 showing a stylet partially inserted and the tubeassembly about to be inserted through a stoma;

FIG. 13 is a view similar to FIG. 12, showing the stylet drivencompletely into the tube assembly to distend the retention ballooncomponent immediately prior to insertion;

FIG. 14 is a view similar to FIG. 13, but showing the balloon componentconfiguration as the balloon passes through the stoma;

FIG. 15 is a side elevational view of a replacement tube assembly in aset of three lengths, the assembly being the shortest of the three andhaving a gauging system embodying features of the inventions imprintedalong its length;

FIG. 16 is a side elevational view of the intermediate lengthreplacement tube assembly in the set of three, also having a gaugingsystem embodying features of the inventions imprinted along its length;

FIG. 17 is a side elevational view of the longest replacement tubeassembly in the set of three, also having the gauging system imprintedalong its length;

FIG. 18 is a side elevational view of a replacement tube assembly inplace in a patient's stoma (in section) with the bolster positionedusing the gauging system of the inventions;

FIG. 19 is a view, similar to FIG. 17, showing a replacement tubeassembly carrying a gauging system which is a variation of that shown inFIGS. 15-18;

FIG. 20 is a view of the replacement tube assembly seen in FIG. 19,showing the opposite side of the tube segment and the gauging system;

FIG. 21 is a longitudinal sectional view through the bolus end of areplacement tube assembly embodying features of another form of theinventions, a form in which the balloon is accessed by an inflation anddeflation lumen;

FIG. 22 is a sectional view taken along line 22--22 of FIG. 21;

FIG. 23 is a sectional view through the set connector for the form ofreplacement tube assembly shown in FIG. 21;

FIG. 24 is a view similar to FIG. 1 illustrating the inventions embodiedin a suprapubic catheter tube assembly;

FIG. 25 is a view similar to FIG. 1 illustrating the inventions embodiedin a PEG tube assembly;

FIG. 26 is a side elevational view of a PEG and insertion tube assemblyembodying features of the present inventions;

FIG. 27 is an enlarged side elevational view of a portion of the PEGtube assembly after it is severed from the assembly of FIG. 25;

FIG. 28 is a side elevational view of a feeding set adaptor ready formating with the PEG tube assembly of FIG. 27; and

FIG. 29 is a side elevational view of the assembled PEG tube after afeeding set adaptor has been mated.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, and particularly to FIG. 1, theinventions disclosed to are embodied here in a replacement gastrostomytube assembly shown generally at 10. The tube assembly 10 is shown inplace, extending through a stoma S in a patient, from a feeding formulasupply tube 11 outside the patient's abdominal wall A to inside thepatient's stomach ST. The stoma S may be formed in a conventional mannerby one of several well-known procedures hereinbefore referred to.

The tube assembly 10 is a replacement tube assembly in the sense thathas hereinbefore been described. The tube assembly 10 is designed to beeasily connected to, and disconnected from, a conventional feedingformula supply tube 11 in a manner hereinafter discussed.

The inventions are illustrated here in a gastrostomy tube assembly.However, as will hereinafter be discussed, the inventions may findequally advantageous application in other tube assemblies, such as PEGand jejunostomy tubes, for example, or other corporeal accessenvironments like suprapubic catheter assemblies.

Referring now to FIG. 2, the replacement gastrostomy tube assembly 10 isseen to comprise a short segment 15 of tube formed of silicone rubberand embodying features of the invention. The gastrostomy tube segment15, which is constructed in a manner hereinafter discussed in detail,has a bolus 16 connected in fluid communication with the tube segment atthe latter's discharge end 17, and a set connector 18 connected in fluidcommunication with the tube segment at the latter's inlet end 19. Thebolus 16 and the set connector 18 are also formed of silicone rubber.

Adjacent the bolus tip 16, and encircling the tube segment 15 near thedischarge end 17, is a tire-shaped balloon 20 which also embodiesfeatures of the invention and will hereinafter be discussed in detail.Suffice it to say at this point that the balloon 20 is filled with afluid medium such as air or water. Air is preferred and, in the presentillustration, is employed.

Approximately intermediate the ends 17 and 19 of the tube segment 15 isa right-angle bolster 21 through which the tube segment passes. Thebolster 21 construction and arrangement on the tube segment 15, whichcomprises additional features of the invention, grips the tube segmentat a selected distance from the balloon 20, and forces the segmentslightly past a right angle configuration so that the set connector 18lies immediately adjacent to the patient's abdomen when in place. Theconstruction and operation of the bolster 21 will also hereinafter bediscussed in detail.

Referring now to FIGS. 3 and 4, the bolus 16 and its connection to thedischarge end 17 of the tube segment 15 is shown in substantial detail.The bolus 16 may be of the design and construction illustrated anddescribed in the Quinn U.S. Pat. No. 5,451,216, assigned to the sameassignee as the present application and invention. The bolus 16comprises a body 30 having a tube 15 receiving section 31, a centralpassage section 32, and a nose section 33.

The tube segment 15, at its discharge end 17, is glued inside thereceiving section 31 of the bolus 16 with a silicone based adhesive. Apassage 35 extending axially through the passage section 32 of the bolus16 is then in continuous fluid communication with the tube 15.

A radially extending discharge port 36 is formed through the bolus fromthe passage 35. It is through this port that enteral feeding dischargetakes place.

The nose section 33 of the bolus 16 has an axial, stylet-receivingpocket 39 formed therein. In this sense the bolus 16 is different thanthat disclosed in the aforementioned Quinn U.S. Pat. No. 5,451,216. Thepocket 39 is designed to receive the tip of a stylet (not shown in thisFIGURE) in a manner hereinafter discussed in detail, both as to the waythe stylet is employed and its purpose.

Referring now to FIGS. 5 and 5A, the portion of the tube segment 15which joins the bolus 16 is shown in enlarged, longitudinal andtransverse sections. The tube segment 15 comprises a silicone body 41containing a stainless steel wire coil spring 42. The coil spring 42extends from the receiving end (not shown) of the tube segment 15 to apoint 43 immediately adjacent, but not within, the balloon 20.Accordingly, the balloon 20 surrounds a tube body portion 45 which isunsupported by the spring 42.

To form the tube segment 15, the coil spring 42 is inserted into anextruded silicone tube. Liquid silicone is introduced into the tube sothat it flows the length of the tube, coating and covering the wire andadhering it to the inside of the tube. The liquid silicone sets tounitize the original tube, the coil spring 42 and the coating into agenerally cylindrical wall having an inner surface 46 and an outersurface 47.

The balloon 20 is tire-shaped, as has been pointed out. It is formed ofconventional silicone film which is 0.030 of an inch thick in thisembodiment. Using the language of vehicle tire construction, itcomprises a casing 51 having an outside diameter of 0.600 inches. Thecasing 51 has, at its inside diameter which corresponds to the outsidediameter of the tube body 41, a pair of beads 52 and 53. The beads 52and 53 are glued to the outer surface of the tube body 41 with asilicone adhesive in a conventional manner.

The balloon 20 is preformed in the shape illustrated. As such, air istrapped in the space 55 when assembled. The beads 52 and 53 are bondedto the tube body 41 to assemble the tube and balloon.

The side-walls 56 and 57 of the tire-shaped balloon casing 51 arepreferably spaced from each other by 0.200 inches from outer surface toouter surface. The side-wall 56 extends perpendicular to the axis of thetube 15 for a distance of 0.100, i.e., it defines a substantially flatouter surface 58 extending outwardly from the bead 52 for 0.100 inches.Connecting the side walls 56 and 57 is the tread wall 59 of the casing51. It defines a semi-circle in cross-section. The radius of thesemi-circle is 0.100 inches.

The aforedescribed balloon 20 configuration provides importantadvantages. Its flat retention surface 58 is 50% of its diameterexternally of the beads 52 and 53. In this shape it is very resistant todistortion when functioning in its tube assembly 10 retaining capacity.It also presents a wide, stable, flat retaining surface 58.

Referring now to FIGS. 6-8, the set connector 18 at the inlet end 19 ofthe tube 15 is shown in enlarged (FIG. 6) and then further enlarged(FIGS. 7 and 8) form. The connector 18 comprises a generally cylindricalfitting 61 also molded of silicone rubber. The fitting 61 has aunitarily formed body 62 and cap 63, with the cap flexibly attached toone end of the body by an easily bendable arm 64.

The fitting body 62 also has an axial passage 65 formed through it.Seated in the passage 65, approximately intermediate its ends, is aconventional slit valve insert 66. The valve insert 66 is also molded ofsilicone and includes a slit 67 which is forced open into a generallyround shape by the feeding supply tube connector tip (not shown) whenthe tip is inserted for feeding purposes. When the tip is removed, andthe valve 66 is subjected to pressure from below, the valve slit 67closes.

The inlet end 19 of the tube 15 is seated in, and glued with a siliconeadhesive to, a cylindrical end section 69 of the passage 65 in thefitting body 62. The cap 63, at the other end of the body 62, includes aplug 71 which is received in the passage 65 when it is desirable todisconnect the replacement tube assembly 10 from the feeding tube 11. Anannular locking shoulder 72 is formed on the plug 71 and is adapted tosnap fit into a corresponding annular locking depression encircling thepassage 65.

Referring again to FIG. 2, and also to FIGS. 9-11, the construction andfunction of the bolster 21 will now be described. The bolster 21comprises a molded silicone rubber body 81 and a molded silicone rubberO-ring 82. The bolster body 81 is formed in a split configuration so asto have two legs, 83 and 84, joined at corresponding one ends by abridge 85. The legs 83 and 84 may be spread to the position shown inFIG. 9 so that the tube segment 15 is essentially straight. In thisposition, the O-ring 82 is positioned off the bolster, freely encirclingthe tube.

When the legs 83 and 84 are brought together, as seen in FIG. 9;, thetube segment 15 is bent slightly past a right angle configuration, i.e.,the angle is slightly less than 90° whereby the tube segment outside thebolster is actually inclined slightly toward the abdominal wall. In thisposition of the legs 83 and 84, the O-ring 82 is snapped into place inan annular depression 86 to maintain the bolster 21 and the tube segment15 is this position.

FIGS. 10 and 11 show the bolster in side and end views, as taken fromFIG. 9. As seen in FIGS. 9-11, the leg 83 is formed with a substantiallysemi-cylindrical trough 87 extending axially along one side of it. Thetrough 87 curves outwardly to terminate at one end at the bridge 85. Atits outer end, the trough 87 becomes a cylindrical passage section 88 asit passes through an annular collar 89 which forms what amounts to afoot on the leg 83. The other leg 84 is also formed with a substantiallysemi-cylindrical trough 91 extending axially along one side of it. Thetrough 91 also curves outwardly to terminate at one end at the bridge85. Immediately adjacent this curve, a cylindrical passage section 92 isformed through the leg 84, perpendicular to the trough 91.

The bolster 21 is fabricated by molding it in a body 81 without legs.The legs 83 and 84 are formed by cutting the body 81 on the L-shapedpath best seen in FIG. 2. It will thus be seen that the normal state ofthe body is with the legs 83 and 84 lying flush against each other. Inthis relationship the two troughs 87 and 91, and the two passagesections 88 and 92, collectively form a generally L-shaped passage 95extending entirely through the bolster, with the passage section 88inclined slightly past a right angle. The leg 84 and, thus, the body 81has a flat bottom or base surface 93. This bottom or base surface 93seats against the patient when the tube assembly 10 is in use, as seenin FIG. 1.

The tube segment 15 is threaded through the passage section 88 in theleg 83 and the passage section 92 in the leg 84 while the legs arespread into the attitude seen in FIGS. 9-11. When it is desirable tobend the tube segment 15 into slightly greater than a right-angle, in amanner hereinafter discussed, the legs 83 and 84 are simply broughttogether and the O-ring 82 snapped in place. Because the tube segment 15has a coil spring 42 built into it, it does not kink and become blockedinside the bolster 21.

Referring now to FIGS. 12-14 and FIG. 1, a replacement gastronomy tubeassembly 10 is shown being prepared for insertion (FIGS. 12 and 13) intothe patient's stomach ST through a preformed stoma S. FIG. 1 shows itinserted and secured. FIG. 14 shows it being inserted (the patient isnot shown here). The stoma S has previously been formed with a PEG. Whenthe PEG is removed, as it normally is after a short period of use, areplacement assembly is inserted.

Referring initially to FIG. 12, a rigid metal stylet 96 of knownconstruction is inserted, tip 97 first, through the set connector 18into the tube segment 15. The stylet 96 is inserted using its handle 98until its tip 97 reaches and seats in the pocket 39 of the bolus 16.Further insertion of the stylet then stretches the balloon 20, as seenin FIG. 13.

According to the invention, the stylet 96 is forced into the tubesegment 15 until it has stretched the balloon out into the configurationshown in FIG. 13. At this point, the volume of the balloon 20 isactually greater that it is in its relaxed form (FIG. 12) so that apartial vacuum forms within the balloon, causing it to collapse inwardto some extent.

With the balloon 20 in a greatly reduced diameter form, the bolus 16 isinserted through the stoma S, followed by the balloon and the lowerportion of the tube segment 15. As the balloon 20 passes through thestoma S it flattens out rearwardly into the configuration shown in FIG.14, thus facilitating passage through the stoma. Once the balloon hasclearly entered the stomach, the stylet 96 is pulled out. The balloon 20expands to its normal size and shape as the tube segment 15 under theballoon becomes shorter and thicker again. The tube assembly 10 is thendrawn outwardly until the flat surface 58 on the outer side 56 of theballoon 20 rests against the stomach wall lining. With the stylet 96completely removed, the plug 71 is inserted into the bore 65 through theset connector for sanitary reasons.

Turning now to the tube measurement system which embodies features ofthe inventions described and illustrated herein, attention is invited toFIGS. 15-17 which a first form of the system is shown. There, threedifferent replacement gastronomy tube assemblies are seen at 10A, 10Band 10C. The tube assemblies 10A, 10B and 10C are identical inconstruction and operation to the assembly 10 hereinbefore described. Aswill be seen, however, the segments 15A, 15B and 15C of gastronomy tubeare progressively longer (by approximately 1.25 centimeters).

In this form of the system, three different replacement assembly lengthsare provided to cover the normal variations in stoma depth encounteredin patients, a range of from approximately 0.75 to 5.00 centimeters. Thetube 15A has a measuring gauge 110 embodying features of the inventionimprinted on its side and covering the shorter-range of stoma depths of0.75 to 2.5 centimeters. The tube 15 has a measuring gauge 111 imprintedon its side and covering the mid-range of stoma depths of 2.0 to 4.0centimeters. The tube 15C has a measuring gauge 112 imprinted on itsside and covering the upper-range of stoma depths of 3.0 to 5.0centimeters.

As will be seen, the measuring gauge 110 comprises two identical sets ofgauge markings 110-1 and 110-2 imprinted on its side. The marking set110-2 is positioned so that corresponding centimeter gradations in the110-1 set (1.0 centimeter, for example) are spaced precisely the lengthof the aforedescribed bolster passage 95 from each other, for reasonshereinafter explained. As will also be seen, the centimeter markings inthe 110-1 set are read right-side-up from the bolus 16 end of theassembly while the centimeter markings in the 110-2 set are readright-side-up from the set connector 18 end, i.e., up-side-down from thebolus end.

The measuring gauges 111 and 112 each have two, identical sets of gaugemarkings also; markings 111-1 and 111-2 in the case of gauge 111 and112-1 and 112-2 in the case of gauge 112. The sets in both gauges are,like the gauge 110, spaced from each other a distance corresponding tothe length of the passage 95 through the bolster 21.

Referring now to FIG. 18, with the tube assembly 111 (for example) inposition so that the balloon 20 rests against the stomach lining, thephysician reads the 2.5 centimeter gauge marking on the tube segment atthe abdomen surface. While this is being done the bolster 21 is in itsopen and displaced position shown in FIGS. 12-14. Bolster legs 83 and 84are then brought together around the silicone tube 15 and held manually.Tube segment 15 is then pulled through the bolster 21 until the paired2.5 centimeter gauge marking is precisely aligned with the end surfaceof the bolster from which it has emerged. The tube segment 25 andbolster 21 position is then as seen in FIG. 18. Then the bolster legs 83and 84 are secured by an O-ring 82. With this done, the physician knowsthat the flat surface 95 of the bolster 21 is resting flush against thepatient's abdomen, but the balloon is not putting inordinate pressure onthe stomach lining--in other words, an ideal fit has been achieved.

Referring now to FIGS. 19 and 20, a second form of measurement systemembodying features of the invention is shown. Here, one length of tube15X is used for the full range of stoma depths. The tube 15X is the samelength as the previously described tube 15C. Unlike the tube 15C,however, it has a full-range measuring gauge 113 on one side of it, withthe indicia in black, and a full range measuring gauge 114 of the otherside of it, with the indicia in red.

The black indicia gauge 113 measures the tube length from the balloon20. The red indicia gauge 114, on the other side of the tube 15X, hascorresponding indicia (3.0 centimeters and 3.0 centimeters, for example)spaced from each other by the length of the bolster passage 95. Thissecond form of gauging system is used in a manner identical to thathereinbefore described in relation to the form.

Referring now to FIGS. 21-23 another embodiment of the gastronomyreplacement tube assembly is illustrated generally at 210. Thereplacement tube assembly 210 is similar to the tube assembly 10hereinbefore described except that it utilizes a tube segment 215 whichhas an inflation/deflation lumen 214 in it and a radial aperture 213connecting that lumen with the inside of the balloon 220.

The inflation/deflation lumen 214 communicates, at its opposite end,with the set connector 218. A lumen access port 264 is formed in thebody 262 of the connector 218 and a silicone rubber slit valve plug 268seals the outer end of that port.

By inserting the round, blunt needle tip T of an inflation/deflationneedle, with a side hole, through the slit valve plug 268, the balloon220 can either be filled with air or evacuated of air. This permits theassembly 210 to be introduced into, or removed from, a stoma even moreeasily.

Referring now to FIG. 24, the inventions disclosed are embodied here ina suprapubic catheter tube assembly shown generally at 310. The assembly310 is substantially identical in construction and operation to thereplacement gastrostomy tube assembly 10 hereinbefore discussed, exceptthat it is introduced into the bladder B through the urinary urethra. Itthen accesses the abdominal wall through a stoma above the bladder inthe pubic area. Accordingly, it is not described independently ingreater detail.

Referring now to FIG. 25, a PEG tube assembly embodying features of theinventions is shown generally at 410. The PEG tube assembly 410 is, inmany respects, identical to the replacement tube assembly 10hereinbefore discussed. To the extent that it is, the PEG tube assembly410 features are not described in great detail. To the extent that itdiffers, the following discussion will be sufficient to an understandingof its construction and operation.

Turning to FIG. 26, the PEG tube assembly 410 or, more precisely, thebulk of it, begins life as a component of a PEG insertion unit 411. ThePEG insertion unit 411 comprises a conventional plastic lead-in tube 412with a solid plastic fitting 413 seated in, and glued to, one end. Aplacement wire 414 is anchored in the tube 412 and protrudes in a loop416 from the other end.

The PEG tube assembly (portion) 410 seen in FIG. 26 comprises a tubesegment 415 identical to that shown at 215 in FIGS. 21-23, with theexception that it has several additional features. As seen in FIG. 27,the tube segment 415 has a deflation lumen 416 extending along itslength, with a radial access port 417 communicating with the retentionballoon 420. The lumen 416 at the end of the tube 415 is plugged at 421(there is no bolus attached).

The tube 415 is, in this illustration, about 25 centimeters long. At apoint 10-15 centimeters from the capped end 421 a thin black marker line425 is imprinted encircling the tube 415. Between the marker line 425and the end 426 of the tube 415 in which the fitting 413 is glued, awide black marker band 430 is imprinted encircling the tube.

Starting from the end 426 of the tube 415, the deflation lumen 416 isplugged at 432 with silicone rubber (after the lumen is initiallyformed) to a point below the band 430 but above the line 425. Below theplug 432, the lumen 416 is open to the balloon 420. It will thus be seenthat the marker band 430 encircles portion of the tube 415 which doesnot contain an open lumen 416.

The PEG tube insertion unit 411 is pulled into the patient's stomach, ina conventional manner, by the placement wire 414. A snare wire (notshown) in a cannula (not shown) which has been inserted into thepatient's stomach by piercing the abdomen and stomach walls is used tosnare the placement wire loop 416 (which has been led in to the stomachthrough the esophagus) and pull it out through the access stoma formedby the piercing. The wire 414, lead in tube 412, and tube 415 continueto be pulled until the retention balloon 420 seats against the stomachwall.

At this point the tube 415 is severed at the marker band 430. A feedingset adaptor 435 (see FIG. 28) is then threaded into the open end of thetube 415 at the marker band 430. Before this is done, however, a bolster441 and retention ring 482 identical to those previously discussed areplaced over the tube 415, as seen in FIG. 29.

As will be seen in FIG. 28, the adaptor 435 is similar to the adaptor 18seen in FIG. 6 except that it is threaded into the tube 415 instead ofbeing glued onto it. This is facilitated by an externally threaded metalfitting 436 which is glued into the body 437 of the adaptor 435. Thethreads 438 on the fitting turn into, and are gripped by, the tube 415.

The tube 415 is now ready to be anchored to the patient's abdomen usingthe bolster 441 and procedure identical to that previously described. Tothis end the tube carries gauging indicia (not shown) which are alsoidentical to those previously described.

After the PEG tube has been used for feeding purposes in a known mannerfor a period, it is removed and replaced with an aforedescribedreplacement tube assembly 10. To do this the bolster 421 is opened. Thenthe tube 415 is cut at the black line 425. This opens the lumen 416. Theretention balloon can now deflate and deform as the PEG tube assembly(or what remains of it after the feeding set adaptor end is severed) 410is pulled out through the stoma.

While preferred embodiments of the invention have been described, itshould be understood that the invention is not so limited andmodifications may be made without departing from the invention. Thescope of the invention is defined by the appended claims, and alldevices that come within the meaning of the claims, either literally orby equivalence, are intended to be embraced therein.

I claim:
 1. A corporeal access tube assembly, comprising:a) a tubesegment having a silicone rubber body; b) said silicone rubber bodyincluding one elongated body portion containing a coil spring extendingalong its length; c) said one elongated body portion and said coilspring forming a generally cylindrical wall having an inner surface andan outer surface, said cylindrical wall in said one elongated bodyportion being supported by said coil spring; d) said silicone rubberbody including another body portion which is coextensive with andadjacent to said one elongated body portion and forms a generallycylindrical wall having an inner surface and an outer surface, saidinner surfaces of said one body portion and said other body portiondefining an unobstructed fluid flow passage through said tube segmentbody, said cylindrical wall in said other body portion having no coilspring support; e) a retention member mounted on and encircling saidother body portion, said retention member including a balloon fastenedto said outer surface of said cylindrical wall in said other bodyportion; and f) a lumen extending through said body portions intocommunication with said balloon, said lumen extending through said onebody portion outside of said coil spring and inside of said outersurface in said one body portion.
 2. A corporeal access tube assembly,comprising:a) a tube segment having a silicone rubber body; b) saidsilicone rubber body including one elongated body portion containing acoil spring extending along its length; c) said one elongated bodyportion and said coil spring forming a generally cylindrical wall havingan inner surface and an outer surface, said spring forming a generallycylindrical wall having an inner surface and an outer surface, saidcylindrical wall in said one elongated body portion being supported bysaid coil spring; d) said silicone rubber body including another bodyportion which is coextensive with and adjacent to said one elongatedbody portion and forms a generally cylindrical wall having an innersurface and an outer surface, said inner surfaces of said one bodyportion and said other body portion defining an unobstructed fluid flowpassage through said silicone rubber body, said cylindrical wall in saidother body portion having no coil spring support; e) said tube segmenthaving an inlet end and an outlet end; f) a fluid flow opening to saidflow passage on one of said tube segment ends and a connector on theother of said tube segment ends; and g) a retention member mounted onand encircling said other body portion; h) said retention memberincluding a balloon comprising a casing having a pair of annular beadsdefining its inner diameter, each of said annular beads being fastenedto said outer surface of the cylindrical wall in said other bodyportion.
 3. The corporeal access tube assembly of claim 2 furthercharacterized by and including:i) a lumen extending through said bodyportions into communication with said balloon.
 4. The corporeal accesstube assembly of claim 2 further characterized in that:i) said fluidflow opening is in a bolus fastened to said other body portion and saidconnector is fastened to said one body portion.
 5. The corporeal accesstube assembly of claim 2 further characterized in that:i) said connectorincludes a unitary body, cap and flexible arm joining said body and cap;j) a connector passage through said body and a one-way valve mounted insaid connector passage; k) said cap including a plug adapted to seat insaid connector passage and seal said connector passage.
 6. The corporealaccess tube assembly of claim 5 further characterized in that:l) saidconnector body is formed of silicone rubber.
 7. The corporeal accesstube assembly of claim 6 further characterized in that:m) said plug hasan annular locking shoulder extending around it; and n) an annularlocking depression is formed in said connector passage for receivingsaid annular locking shoulder.
 8. A corporeal access tube assembly,comprising:a) a segment of tube having an inlet end and a discharge end;b) said tube segment including a cylindrical body wall formed ofrubber-like material and having an outer surface and an inner surface;c) said inner surface defining a generally cylindrical fluid flowpassage which is unobstructed through said tube segment between saidinlet and discharge ends; d) the body wall in a portion of said tubesegment containing an elongated coil spring which supports said wall insaid portion of said tube segment; e) the body wall in another portionof said tube segment containing no supporting coil spring; f) a fluidflow opening to said tube segment passage on one of said tube segmentends and a connector on the other of said tube seen ends; g) a balloonencircling said other portion of said tube segment and connected to saidtube segment, said balloon comprising a casing having a pair of annularbeads defining its inner diameter, each of said annular beads beingfastened to said outer surface of said cylindrical body wall in saidover portion; and h) a balloon deflation lumen extending longitudinallythrough said tube segment between said inlet end and said balloon.
 9. Afeeding tube assembly comprising:a) a tube segment having an inlet endand a discharge end; b) said tube segment including a body formed ofrubber-like material and having a cylindrical wall with an outer surfaceand an inner surface; c) said inner surface defining a generallycylindrical fluid flow passage through said tube segment; d) the body inone portion of said tube segment containing an elongated coil springwhich supports said cylindrical wall in said one portion of said tubesegment; e) the body in another portion of said tube segment containingno supporting coil spring; f) a balloon encircling said other portion ofsaid tube segment and connected to said tube segment, said ballooncomprising a casing having a pair of annular beads defining its innerdiameter, each of said inner beads being fastened to said outer surfaceof said cylindrical wall in said other body portions; g) a bolusfastened to the discharge end of said tube segment; and h) a connectorfastened to the inlet end of said tube segment.
 10. The feeding tubeassembly of claim 9, further characterized in that:j) said bolus has anaxially extending pocket formed therein for receiving the tip of astylet.
 11. A feeding tube assembly, comprising:a) a tube segment havingan inlet end and a discharge end; b) said tube segment including acylindrical body wall formed of rubber-like material and having an outersurface and an inner surface; c) said inner surface defining a generallycylindrical passage through said tube segment; d) a wall supportstructure associated with said body wall formed of rubber-like materialand having an outer surface and an inner surface; c) said inner surfacedefining a generally cylindrical passage through said tube segment; d) awall support structure associated with said cylindrical body wall alongonly a portion of said tube segment; e) a balloon encircling anotherportion of said tube segment containing no wall support structure andconnected to said tube segment, said balloon comprising a casing havinga pair of annular beads defining its inner diameter, each of saidannular beads fastened to said outer surface of the cylindrical bodywall in said other body portion of said tube segment; f) a bolusfastened to the discharge end of said tube segment; and g) a connectorfastened to the inlet end of said tube segment; h) said bolus having apocket formed therein for receiving the tip of a stylet; i) said otherbody portion of said tube segment being stretchable by the action of astylet seated in said pocket so as to stretch the balloon axially andreduce its dimensions radially.
 12. The feeding tube assembly of claim11 further characterized in that:i) said rubber-like material issilicone rubber.
 13. The feeding tube assembly of claim 12 furthercharacterized in that:j) said wall support structure comprises a coilspring.
 14. A gastrostomy tube assembly adapted to extend into apatient's stomach through a stoma and be retained therein by a retentionmember inside the stomach, comprising:a) a tube segment having a bodyformed of rubber-like material; b) said body including one elongatedbody portion containing a coil spring extending along its length; c)said one elongated body portion and said spring forming a generallycylindrical wall having an inner surface and an outer surface, saidcylindrical wall in said one elongated body portion being supported bysaid coil spring, at least a portion of said one elongated body portionadapted to be disposed in the stoma when a retention member is retainingthe tube assembly; d) said body including another body portion which iscoextensive with and adjacent to said one elongated body portion andforms a generally cylindrical wall having an inner surface and an outersurface, said wall in said other body portion having no coil springsupport whereby it can be readily deformed radially inwardly; e) saidtube segment passage having an inlet end and an outlet end; f) a fluidflow opening to said tube segment passage on one of said tube segmentends and a connector on the other of said tube segment ends; and g) aretention member mounted on and encircling said other body portion.